TP SCAN allowes you to scan any 1 TRANSPONDER on any given SAT.Each SAT has between 5 to 30 TRANSPONDERS.
Its helpful if you know the TRANSPONDER a particular channell is on.That way you dont have to do a total sat scan.
You can SCAN each TRANSPONDER on each SAT as well to acheive the same as a SAT SCAN.
A blind scan first scans for all available TRANSPONDERS on that SAT,saves them, then SCANS each TRANSPONDER for the channels.There may be 1 to 30 or more channels on each TRANSPONDER.